Solar energy is an abundant, renewable, sustainable, clean, and ecologically rational energy source. For example, one hour of solar energy hitting the Earth can be sufficient to meet the current world demand for approximately one year. The sun could potentially provide a perpetual energy supply. Many technologies have been developed which attempt to harvest solar energy in a cost-effective way and at large scales of economy. Despite advances in solar energy technologies, there are still difficulties in cost-effectively and reliably capturing the solar energy from the sun.
The confluence of recent advances in PhotoVoltaic (PV) cell technologies and advanced optical designs has resulted in increased capabilities for efficient and affordable solar electricity generation at high concentrations. Commercial multi-junction PV cells have demonstrated efficiencies as much as 40% and greater. This high efficiency is typically realized at high flux levels such as may be equivalent to hundreds or even thousands of suns. At such a high concentration, the cost of PV cells can be sufficiently low for various applications despite being more expensive than traditional PV or thin-film cells with a same size of area.
High concentration photovoltaic (HCPV) technologies are often considered to be an efficient approach to convert solar energy directly to electric power. However, costs of producing high concentration PV modules are somewhat high, which may be due at least in part to ineffective optical designs that impose a stringent optical alignment tolerance for system components. The ineffective optical designs can lead to high costs for manufacturing, assembly, transport, installation and maintenance. Providing a practical and affordable solar energy system can come closer to reality with an improvement in optical design techniques.